When I was a kid, I was lucky enough to get to take a tour of the Mrs. Baird's Bread factory. I was mesmerized. The smells, the conveyor belts, the slice of warm bread I got to eat, the factory worker with 3 missing fingers because she got too close to the bread slicer. Aaaugh! It's all still so fresh in my mind.

But seriously, a factory tour is an amazing way to spend a few hours on a hot summer day. It's so important for kids to understand where things come from, and it's fascinating to see the people and machines working together harmoniously (hopefully) to create the goods we use every day.
Factory Tours USA is a great website that lists factories that offer tours by state or by category. From teddy bears to motorhomes to cheese to pianos, you'll be shocked to see how many factories offer tours and most are free. You can also call facilities that you know are in your area to see if they offer an inside glimpse of their manufacturing process.
(Top image: Tillamook Cheese Factory, free self-guided tours available daily year-round. Bottom image: Heath Ceramics, Sausalito, CA, free tours Friday-Sunday, call to make reservations)

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If you live in the WI/IL border area, I highly recommend the Jelly Belly factory tour. Best part? FREE JELLY BEANS!!
Funny...we were just on holidays in Penticton BC, and went to the Summerland Sweets (Jam, syrup etc) "Factory Tour" (advertised on their website). They showed us to a room, popped in a DVD about their AMAZING quick cooling process (etc) and offered free samples. SO not what I was hoping for. But a funny story. Jelly Belly factory sounds cool.
I second the Jelly Belly tour- we have a plant in Fairfield, near San Francisco, which is fun. Before they closed the Hershey factory in Oakdale that was a fun one, too. I used to think I was in the Willy Wonka movie. :)
I distinctly remember there was a school teachers strike the year I was supposed to start 6th grade. My mom grew so desparte for things to do we starting touring every factory in the Seattle area. Boeing was obviously great, and Seaman's candy. But the real highlight? A pickle factory! They were so excited to have visitors they sent us home with cases of pickles at the end of the day.
In elementary school, we took a factory tour of the Philip Morris cigarette factory in my hometown. And we got souvenir pens with all the cigarette logos on them. That is one of my more hilarious 'how times have changed' memories. But factory tours that are actually kid-appropriate are a great idea.
The Blue Bell Factory tour is pretty fun. It's in Brenham, TX, about an hour drive NW of Houston.
They have you watch a cheesy video & then take a tour of the factory. It's not very long though. Video & tour took about 30min tops. Plus, free ice cream at the end!
I'm 99% certain the photo above is at the Tillamook Cheese Factory on the Oregon Coast! It's definitely worth a stop... if only to be able to snack on sqeeky cheese curds and choose from ALL of Tillamook's ice cream flavors.
Don't forget about the US Mint, too!
@bendable: LOL! I'm surprised they didn't give you candy cigarettes!
Pssh - just saw the photo credit!
The Ben and Jerry's Factory tour in Waterbury, VT, is great. They show a short video about B&J history, they walk through the factory where you can see every step of the process. With free samples at the end!
Cracking up at the cigarette factory tour. That's like something from an episode of The Simpsons.
Tillamook is FANTASTIC. I loved that tour. The Jelly Belly tour is also fun but my 2 year old did not appreciate it.
However, should your 2 year old fall out of his stroller and land directly on his forehead which makes a loud wet crack like a watermelon breaking open on pavement, and start screaming and crying and you start crying and freaking out because you couldn't catch him because you have a broken ankle which you got 2 days ago hiking in the Redwoods, then the workers at the Jelly Belly gift shop will be ever so helpful and pick up your screaming son and take him over to the counter and give him a huge free stuffed Jelly Belly and a handheld fan that lights up and gets him to stop screaming, in addition to providing ice packs and sympathy to your poor hurt mom-feelings. They will also help you find a doctor if you are from out of the area.
True story.
I knew that was the Tillamook factory as soon as I saw the photo! It is always a stop on our trip to the Oregon coast. There's a petting zoo nearby too.
What a great idea. Im obsessed with figuring out how things work/are made. Im not sure if my daughter would be as interested as me. I wish this was up at the beginning of summer. My little one starts school Monday.
I second the Ben and Jerry's factory tour in Vermont. Not too long, but definitely worth it. Outside, in the BEAUTIFUL rolling countryside, they have a small "graveyard" with headstones saying all the names of the flavors they've discontinued. It's pretty cute.
Also, if you're with a group of adults, several breweries give pretty cool tours. The one in Boston (I think it's Sam Adams??) gives an awesome tour where you can see them bottling the beer and at the end you get to try tons of different beers and even the really rare ones (like the triple bock). I'm not a beer person, but my husband and I went with some out of town friends and we all enjoyed it.